Union dyeing of mixed fabrics of cellulose ester and animal fibers with alkaline reduced vat dye solutions containing swelling agents



Patented Oct. 3, 1950 UNITED STATES UNION DYEING OF MIXED FABRICS OF ..OEL-.

LULOSE ESTERAND ANIMAL FIBERS WITH ALKALINE REDUCED VAT DYE SOLUTIONS CONTAINING SWELLING AGENTS George C. Ward and William '1. Haggerty, Jr., 1 Cumberland, MIL, assignors'to Celanese Corporation of America, a corporation of Delaware N Drawing. Application April Serial No. 22,235

9 Claims. (Cleaaud] This invention relates to the union dyeing with vatdyestuff of mixed textile materials having a basis of a cellulose acetate or other organic acid ester of cellulosetextile material in' admixture with animal fibers. continuation-in-part of our application S. N. 804, filed January 6, 1948.

An object of this invention is the provision of an improved process for the union dyeing of mixed materials comprising cellulose acetate or other organic acid ester of cellulose textile material and animal fibers, such as wool or silk with vat dyestuffs whereby even, level union dyed effects may be obtained efficiently and economically.

Another object of this invention is to provide a novel process for the union dyeing of mixed textile materials comprising cellulose acetate or other organic acid ester of cellulose materials in admixture with animal fibers such as wool or silk in even, level shades fast to light, washing and acid fading.

Other objects of this invention will appear from thefollowing detailed decription.

i Theunion dyeing of textile materials comprising mixtures of cellulose acetate or other organic acid ester of cellulose materials and animalfibers such as wool or silk in solid shades has not heretofore been entirely satisfactory froma commercial point of view. While union dyeings Of a mixture of'cellulose acetate and animal fibers, such as wool, for example, employing direct dyeing dyestufis for cellulose acetate may be obtained, these direct dyeing dyestufis normally act only to stain the wool and the color of the wool portion of the.

union material is not sufiiciently light fast to be entirely satisfactory. Although the vat dye stuffs, on the other hand, are noted for their fastness properties, the use of said vat dyestuffs for the dyeing of mixed materials comprising cellulose acetate or other organic acid ester of cellulose textile material and animalfibers has been quite objectionable since said dyestuffs are usually applied in a strongly alkaline vat and the presence of the alkali therein has a pronounced sjaponiiying action on the cellulose ester materials. The saponification not only produces a loss in weight of the cellulose ester materials but deleteriolusly affects the luster, strength and the dyeing properties of the materials as well. Various procedures have been suggested-for the dyeing of hnion materials comprising cellulose acetate or other organic acid ester of cellulose ma terialci'and animal fibers with leuco vats of reduced alkalinity whereby these difilcultiesmay This application is a be avoided but none'of these has'proven to be commercially acceptable. For one thing not only do "said procedures-1 permit but a very limited range of shades to be dyed satisfactorily but they also involve a drying of the impregnated textile material prior to oxidation, which step substantially decreases the speed of production. Ac-

cordingly, the production of satisfactory union dyeings of mixtures of cellulose acetate with wool or silk with vat dyes has been a problem in the dyeing art.

I We have now found that the union dyeing of cellulose acetate or other organic acid ester of cellulose textile material in admixture with animalfibers, such as silk or wool, may be effected rapidly and in a continuous manner with vat dyestuffs and even, level shades obtained by treating said mixed textile materials with a dyebath comprising an aqueous alkaline solution of an alkali metal salt of a leuco vat dyestuff whose alkalinity is controlled to a pH of 10.5 to 11.5 containinga salt of thiocyanicacid and 10 to 30% by 'weig-ht' of diacetone alcohol at a temperature of '55 to 0., rinsing the treated textile ma-.

example Ponsol Brilliant Green 4G, Ponsol Jade.

Green (0. I. No. 1101) Indanthrene Brown GWF (C. I. No. 1152) or Calcoloid Printing Yellow GC satisfactory union dyeings of mixed cellulose acetate and wool fabrics are obtained by employing an aqueous dye bath containingabout 20% by weight of diacetone alcohol. With vat dyestuffs such as Cibanone Grey RA, Sulfanthrene Scarlet BBN or Midland Vat Blue R (C. I. No. 1183), a concentration of about 10% by weight of diacetone alcohol is sufficient to produce an even, level union dyeingof amixed material containing cellulose acetate and wool fibers. With Indanthrene Golden Orange (C. I. No. 1096), the diacetone alcohol concentration should be about 25% by weight in order to obtain a union dyeing of a mixed cellulose acetate and wool material.

By suitably varying the proportion of diacetone alcohol present in the dyebath, the cellulose acetate material may also be caused. to be. dyed 'in heavier shades than the animal fibers if certain novel effects are desired. Usually, for any given dyestufif, a greater concentration of diacetone alcohol than is usually employed for producingunion dyeings in solid, even shades is necessary in the dyebath when it is desired to dye the cellulose acetate in the mixed material a deeper shade than the wool or silk fibers present. Our process may, of course, be employed for the dyeing of textile materials consisting only of wool or silk or of an organic acid ester of cellulose such as cellulose acetate.

As examples of the salts of thiocyanic acid which may be satisfactorily employed in forming the leuco vat dyebaths employed in our novel vat dyeing process, there may be mentioned sodium thiocyanate, potassium thiocyanate, ammonium thiocyanate and zinc thiocyanate. The thiocyanic acid salt may be employed in amounts of from 0.5 to based on the weight of the dyebath, although optimum results are obtained employing about 3% by weight of the thiocyanic acid salt. Satisfactory dyeing is readily achieved by subjecting the material to be dyed to the action of the alkaline leuco vat dyebath for a period of from only seconds to 1 and not more than about 2 minutes before rinsing and oxidation. Our novel dyeing process, accordingly, permits exceedingly rapid penetration and dyeing.

After the textile material has been suitably impregnated with the dyebath the impregnated textile material is then rinsed directly Without any intermediate drying and the leuco vat dyestufl; on the wet, rinsed material is then oxidized to the colored form. A suitable oxidizing bath may be employed such as an aqueous solution containing from about 0.5 to 5% by weight of sodium perborate maintained at a temperature of to 65 C. and subjecting the impregnated textile material to the action of the oxiding bath for from about to 10 minutes. Following the oxidation Example I A dyebath is formed by adding 5 parts by weight of Midland Vat Blue R paste (Color Index No. 1183), i. e. 5,7,5-tribromoindigotin, to 60 parts by weight of water containing 1 part by weight of sodium hydroxide, 2 parts by weight of sodium hydrosulfite and 1 part by weight of a suitable detergent or wetting agent. The oleic acid ester of a sulfonated aliphatic compound, such as ethylene glycol, has been found to be satisfactory as a wetting agent. The dyestuif is vatted in the bath at C. for about 15 minutes, or until a clear solution is obtained. 15 parts by weight of sodium thiocyanate are dissolved in 340 parts by weight of water, the solution obtained added to the reduced dyebath and A mixed cellulose acetate and wool fabric containing about 50% by weight of wool is immersed in the dyebath for 15 seconds with the dyebath maintained at a temperature of 58 C. The

treated fabric is removed, rinsed in warm water ill.

4 and, without drying, the dyestuff 0n the wet, rinsed fabric, is then oxidized by immersing the fabric for 2 minutes in a 1% by weight aqueous solution of sodium perborate maintained at 50 C. After oxidation of the leuco vat dye to the colored form is completed, the dyed fabric is then rinsed, soaped and dried. The mixed fabric is union dyed in a uniform blue shade by our process and both the wool and cellulose acetate fibers Example 11 An alkaline dyebath is formed in the manner described in Example I employing, however, 5 parts by weight of Ponsol Jade Green Double Paste (C. I. No. 1101) i. e. dimethoxy-dibenzanthrone, and about parts by weight of diacetone alcohol. The pH of the dyebath is between 10.5 and 11.5.

A mixed cellulose acetate and wool fabric containing about 50% by weight of wool is treated in the dyebath for 15 seconds with the dyebath maintained at a temperature of 58 C. the treated fabric removed, rinsed in warm water and, without drying, the dyestuff on the wet, rinsed fabric is then oxidized by immersion for 2 minutes in a 1% by weight aqueous solution of sodium perborate maintained at 50 C. After oxidation of the leuco vat dye to the colored form, the dyed fabric is then rinsed, soaped and dried. The mixed fabric is dyed in a uniform bright green shade, both the wool and cellulose acetate fibers being dyed in an even and level manner, The dyed fabric obtained is fast to light, no change being observed even after 40 hours exposure in the Fadeometer," fast to washing at 160 F. and exhibits a resistance to acid fading of 2 units in accordance with the standard A. A. T. C. C. test.

When a mixed cellulose acetate and silk fabric containing about 40% by weight of silk is dyed with the dyebath, in the manner described above, a Very satisfactory union dyed fabric is obtained.

Ezmmple II I An alkaline leuco vat dyebath is formed in the manner described in Example I employing, however, 5 parts by weight of Indanthrene Golden Orange Paste (C. I. No. 1096), i. e. pyranthrone, and about parts by weight of diacetone alcohol to form the dyebath. The pH of the dyebath obtained is between 10.5 and 11.5.

V A mixed cellulose acetate and wool fabric containing about 30% by weight of wool is treated in the dyebath for 15 seconds with the dyebath maintained at a temperature of 58 C. the treated fabric removed, rinsed in warm water and, without drying, the dyestuff on the wet, rinsed fabric, is then oxidized by immersion for 2 minutes in a 1% by weight aqueous solution of sodium perborate maintained at 50 C. After oxidation of the leuco vat dye to the colored form, the dyed fabric is then rinsed, soaped and dried. Themixed fabric is dyed in a uniform, golden orange shade. both the wool and cellulose acetate fibers being dyed to the same shade. The dyed fabric is fast to light, no change being observed even after 40 hours exposure in the Fadeometer, fast to washing at F. and exhibits a resistance to acid fading of 2 units in accordance with the standard A. T. C. 0. test.

This dyebath may also be employed for the production of union dyeings on mixed cellulose acetate and silk fabrics.

It is to be understood that the foregoing detailed description is given merely by way of illustration and that many variations may be made therein without departing from the spirit of our invention.

Having described our invention, what we desire to secure by Letters Patent is:

1. Process for the union dyeing of textile materials With vat dyestuffs, which comprises treating a mixed textile material consisting of an organic acid ester of cellulose textile material in admixture with an animal fiber material with an aqueous alkaline solution of an alkali metal salt of a leuco vat dyestuif at a pl-f of 10.5 to 11.5 containing a salt of thiocyanic acid and 10 to 30% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material directly after treatment, and oxidizing the leuco vat dyestuff on the wet, rinsed fabric.

2. Process for the union dyeing of textile materials with vat dyestuffs, which comprises treating a mixed textile material consisting of an organic acid ester of cellulose textile material in admixture with Wool fibers with an aqueous alkaline solution of an alkali metal salt of a leuco Vat dyestuff at a pH of 10.5 to 11.5 containing a salt of thiocyanic acid and 10 to 30% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material di rectly after treatment, and oxidizing the leuco vat dyestuif on the wet, rinsed fabric.

3. Process for the union dyeing of textile mate rials with vat dyestuffs, which comprises treating a mixed textile material consisting of an orgam'c derivative of cellulose textile material in admixture with silk fibers with an aqueous alkaline solution of an alkali metal salt of a leuco vat dyestuff at a pH of 10.5 to 11.5 containing a salt of thiocyanic acid and 10 to 30% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsin the treated material directly after treatment and oxidizing the leuco vat dyestuff on the wet, rinsed fabric.

4. Process for the union dyeing of textile materials with vat dyestuffs, which comprises treating a mixed textile material consisting of a cellulose acetate textile material in admixture with wool fibers with an aqueous alkaline solution of an alkali metal salt of a leuco vat dyestuff at a pH of 10.5 to 11.5 containing sodium thiocyanate and 10 to 30% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material directly after treatmentand oxidizing the leuco vat dyestuff on the wet, rinsed fabric.

5. Process for the union dyeing of textile materials with vat dyestuffs, which comprises treating a mixed textile material consisting of cellulose acetate textile material in admixture with wool fibers with an aqueous alkaline solution of an alkali metal salt of a leuco vat dyestuif at a pH of 10.5 to 11.5 containing from 0.5 .to 5% by weight of sodium thiocyanate and 10 to 30% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material directly after treatment and oxidizing the leuco vat dyestuif on the wet, rinsed fabric.

6. Process for the union dyeing of textile materials with vat dyestuffs, which comprises treat ing a mixed textile material consisting of a cellulose acetate textile material in admixture with wool fibers for not more than about 2 minutes with an aqueous alkaline solution of an alkali metal salt of a leuco vat dyestuff at a pH of 10.5 to 11.5 containing from 0.5 to 5% by weight of sodium thiocyanate and 10 to 30% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material directly after treatment, and oxidizing the leuco vat dyestuff on the wet, rinsed fabric.

7. Process for the union dyeing of textile materials with vat dyestuffs, which comprises treating a mixed textile material consisting of a cellulose acetate textile material in admixture with wool fibers for not more than about 2 minutes I 'with an aqueous alkaline solution of an alkali metal saltof leuco 5,7,5-Jribromoindigotin at a pH of 10.5 to 11.5 containing from 0.5 to 5% by weight of sodium thiocyanate and about 10% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material directly after treatment, and oxidizing the leuco vat dyestuff on the wet, rinsed fabric.

8. Process for the union dyeing of textile materials with vat dyestuffs, which comprises treating a mixed textile material consisting of a cellulose acetate textile material in admixture with wool fibers for not more than about 2 minutes with an aqueous alkaline solution of an alkali metal salt of leuco dimethoxy-dibenzanthrone at a pH of 10.5 to 11.5 containing from 0.5 to 5% by weight of sodium thiocyanate and about 20% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material directly after treatment, and oxidizing the leuco vat dyestuff on the wet rinsed fabric.

9. Process for the union dyeing of textile materials with vat dyestuffs, which comprises treating a mixed textile material consisting of a cellulose acetate textile material in admixture with wool fibers for not more than about 2 minutes with an aqueous alkaline solution of an alkali metal salt of leuco pyranthrone at a pH of 10.5 to 11.5

, containing from 0.5 to.5% by weight of sodium thiocyanate and about 25% by weight of diacetone alcohol maintained at a temperature of 55 to 65 C., rinsing the treated material directly after treatment. and oxidizing the leuco vat dyestuff on the wet, rinsed fabric.

GEORGE o. WARD. 7 WILLIAM T. HAGGERTY, JR.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS France June 26, 1939 

1. PROCESS FOR THE UNION DYEING OF TEXTILE MATERIALS WITH VAT DYESTUFFS, WHICH COMPRISES TREATING A MIXED TEXTILE MATERIAL CONSISTING OF AN ORGANIC ACID ESTER OF CELLULOSE TEXTILE MATERIAL IN ADMIXTURE WITH AN ANIMAL FIBER MATERIAL WITH AN AQUEOUS ALKALINE SOLUTION OF AN ALKALI METAL SALT OF A LEUCO VAT DYESTUFF AT A PH OF 10.5 TO 11.5 CONTAINA SALT OF THIOCYANIC ACID AND 10 TO 30% BY WEIGHT OF DIACETONE ALCOHOL MAINTAINED BY A TEMPERATURE OF 55 TO 65* C., RINSING THE TREATED MATERIAL DIRECTLY AFTER TREATMENT, AND OXIDIZING THE LEUCO VAT DYESTUFF ON THE WET, RINSED FABRIC. 